Facile synthesis of highly thermal-stable doped alumina with high surface area by low temperature solid-state reaction

Alumina and M-(La, Ba, Si) doped alumina were prepared by a facile low temperature solid-state reaction route and using cheap inorganic raw materials without any surfactants, in which only a harmless byproduct to environment was NH4Cl. The results show that all the prepared samples have a mesoporous structure and the BET surface area of as-synthesized alumina precursor has reached 326 m(2)/g. Si-doped alumina exhibits remarkable thermal stability and high surface area (135-163 m(2)/g) and the Ba-doped alumina have a large pore volume (0.44-0.95 cm(3)/g) even after calcination at 1100 degrees C for 10 h. The nature of dopants and their concentrations have a significant influence on the textural properties and morphologies of M-alumina. The precursor synthesized can be converted to lower crystal ammonium aluminum carbonate hydroxide (AACH) by further thermal treatment. Si-doped alumina prepared by alumina from thermal decomposition of AACH possessed the superior thermal stability, and the surface area of 25%Si-Al2O3 calcined at 1100 degrees C for 10 h can reach 176 m(2)/g. This facile synthetic route of alumina is an environmental friendly and convenient, and can be used in synthesis of other metal oxide porous materials. (C) 2017 Elsevier B.V. All rights reserved.